AssemblyAI
Multimodal & Perception · Free + paid
Speech AI models for transcription and understanding
At a glance
- Made by
- AssemblyAI
- Korean
- None (English and a few others only)
- API
- Yes
- Available on
- API
What is AssemblyAI?
AssemblyAI offers speech-to-text (STT) APIs for pre-recorded files, real-time, and synchronous use, as well as a voice agent API. Pre-recorded STT supports 99 languages and provides speaker diarization, PII masking, and more, while streaming STT delivers about 150ms (p50) latency over WebSocket. It also has speech understanding such as summarization, sentiment, and topic detection, guardrails for PII and content moderation, and an LLM Gateway for using multiple LLMs through the same API. It can be integrated with Python and TypeScript SDKs and an MCP server.
- Pre-recorded file STT API (99 languages, speaker diarization, PII masking)
- Real-time streaming STT (about 150ms p50 latency)
- Synchronous STT (short audio up to 120 seconds)
- Dictation API (transcribe, then format with an LLM)
- Voice Agent API (voice agent integrating STT, LLM, and TTS)
- Speech Understanding (summarization, sentiment, topic detection)
- Guardrails (PII handling and content moderation)
- LLM Gateway (multiple LLMs through the same API)
Who uses AssemblyAI and for what
- Building voice agents
- AI meeting notes and call analytics
- Medical transcription
Pricing
What you get for free — Yes ($50 free credit, no card required)
| Plan | Price | Main limits |
|---|---|---|
| Universal-3.5 Pro (pre-recorded files) | $0.21 | Per audio hour, 18 languages |
| Universal-2 (pre-recorded files) | $0.15 | Per audio hour, 99 languages |
| Universal-3.6 Pro Realtime (streaming) | $0.45 | Base rate per session hour |
| Universal-Streaming English/Multilingual | $0.15 | Per session hour |
| Voice Agent API | $4.5 | Per session hour ($0.075/min), STT, LLM, and TTS included |
| Custom | Contact sales | Custom limits and concurrency, contact sales |
Checked on the official pages on 2026-10-14. Prices and features can change, so check the official site again before paying. · Official pricing page
AI tools similar to AssemblyAI (alternatives)
AssemblyAI vs. alternatives at a glance
| AI | Pricing | Combos on the map | Connected tools | Free | Cheapest monthly | Korean |
|---|---|---|---|---|---|---|
| AssemblyAI | Free + paid | 0 | 5 | Yes | — | No |
| Azure Speech | Free + paid | 0 | 5 | Yes | — | Yes |
| Deepgram | Free + paid | 0 | 5 | Yes | — | No |
| Parakeet | Free | 0 | 5 | — | — | No |
| superwhisper | Free + paid | 0 | 5 | Yes | — | No |
4 of these 5 tools have a free plan.
Combo and connection counts are based on the relationships recorded on AI Galaxy Map (2026-10-26); they are not a quality ranking.
AssemblyAI on AI Galaxy Map
- One of 22 AI tools in the Multimodal & Perception field.
- Connected to 5 other tools — #11 in its field.
Frequently asked questions
Can I use AssemblyAI for free?
Yes ($50 free credit, no card required). Prices can change, so check the official site before paying.
What AI can I use instead of AssemblyAI?
Tools that do the same job, such as Azure Speech, Deepgram, Parakeet, superwhisper, are connected to it on the map.
Can I use AssemblyAI in Korean?
None (English and a few others only)
Sources (official pages)
- https://www.assemblyai.com/
- https://www.assemblyai.com/docs/
- https://www.assemblyai.com/llms/pricing.md/
- https://www.assemblyai.com/pricing/
Checked on the official pages on 2026-10-14. Prices and features can change, so check the official site again before paying.